Dr David Themens PhD

David R. Themens

Department of Electronic, Electrical and Systems Engineering
Associate Professor

Contact details

Address
University of Birmingham
Edgbaston
Birmingham
B15 2TT
UK

David Themens is an Associate Professor in Space Environment in the Space Environment and Radio Engineering (SERENE) group in the School of Engineering

David primarily undertakes research in modelling and mitigating the impacts of space weather on radio communications and navigation systems. More specifically, David explores the effects of changes in the ionosphere, a layer of plasma in the earth’s upper atmosphere, on these systems. His work includes exploring the synergistic properties of different earth observation instruments, measurement technique development, data assimilation, empirical modelling, ionospheric physics, and HF/UHF raytracing.

David is the principal developer of the Empirical Canadian High Arctic Ionospheric Model (E-CHAIM).

Qualifications

Lecturer in Space Environment

  • Associate Professor in Space Environment, University of Birmingham, 2022
  • PhD in Physics University of New Brunswick, 2018
  • MSc in Atmospheric and Oceanic Science, McGill University, 2013
  • BSc (Hons) in Physics, University of New Brunswick, 2011

Biography

Dr. David R. Themens earned his B.Sc. (Hon. Phys.) from the University of New Brunswick in 2011, under the supervision of Prof. P.T. Jayachandran, where his research focused on the development of Global Navigation Satellite System (GNSS) receiver calibration and the validation of ionospheric models.

David completed his M.Sc. in Atmospheric and Oceanic Science at McGill University in 2013, under the supervision of Prof. Frédéric Fabry. At McGill, David participated in the development of a scanning microwave radiometer system, designed to make large-scale volumetric measurements of atmospheric water vapour and temperature, which are vitally important to weather forecasting and severely under-observed. David’s research focused on instrument simulation and information theory, attempting to determine the optimal operating frequencies of the instrument and assessing the distribution of information measured by the system. His work demonstrated that traditional use of these instruments discarded large quantities of information, such that simple modifications to traditional measurement inversion methods could produce a more than 10,000% increase in the information provided by scanning microwave radiometers.

David completed his Ph.D. in Physics at the University of New Brunswick in 2018. His Ph.D. research focused on the development of the Empirical Canadian High Arctic Ionospheric Model (E-CHAIM), a high-latitude alternative to the use of the International Reference Ionosphere (IRI) in modelling ionospheric electron density, necessary for HF/UHF signal propagation modelling. During his Ph.D., David acquired a pair of contracts with Defence Research and Development Canada (DRDC) to expand his E-CHAIM model and develop an operational near-real-time data assimilation system for use with Over-The-Horizon-Radar. This continued into David’s postdoctoral research, where he served as Project Lead for the Canadian High Arctic Ionospheric Models (CHAIMs) contracts. For access or information about E-CHAIM and its related systems, check the system website here: https://e-chaim.chain-project.net/

David has a passion for data science and a, perhaps unhealthy, fascination with ionosondes.

Teaching

  • LI Space System Engineering and Design B
  • LH Space Mission Analysis and Design
  • LM Space Environment

Postgraduate supervision

David is always looking for new Ph.D. students interested in the ionosphere, data assimilation, and radio propagation.

Interested students should send David a complete CV and a one-page (single sided) statement on their research interests.

Research

David’s research focuses on four main topics: ionospheric modelling, physics, measurement techniques, and radio propagation.

David’s main physics research focuses on the interaction between the ionosphere and the atmosphere. His interests concern the degree to which lower atmospheric forcing drives variability within the ionosphere and the interactions between the ionosphere and thermosphere.

David is also actively expanding and improving upon his E-CHAIM ionospheric electron density model, having recently lead the development of a near-real-time and reanalysis data assimilation system, based on E-CHAIM, and having developed an auroral particle precipitation module and a quiet D-Region for the model.

David’s modelling research is applications-oriented, focusing on the mitigation of ionospheric impacts on radio communications, Over-The-Horizon-Radar (OTHR), and navigation systems. To this end, David conducts ionospheric raytracing for HF and UHF signals to assess the impacts of the ionosphere on these systems and develop mitigation strategies.

David is also highly interested in exploring novel ways to extract new information from existing instruments and infrastructure using non-linear data assimilation techniques.

Other activities

  • International Association of Geodesy (IAG) - Global Geodetic Observing System (GGOS) Joint Study Group - Understanding Ionospheric and Plasmaspheric Processes – Co-Chair (September 2023 - Present), Member (2019 – Present)
  • URSI Commission G Early Career Representative (August 2023 – August 2029)
  • URSI Data Assimilation Working Group – Chair (August 2023 – Present)
  • International Association of Geomagnetism and Aeronomy (IAGA) Geospace Data Assimilation Working Group (GeoDAWG) – Co-Chair (July 2023 – July 2027)
  • International GNSS Service (IGS) Ionosphere Working Group – Member: 2022 – Present
  • Canadian Space Agency Solar Terrestrial Science Advisory Committee – Member: 2022 – Present
  • URSI Working Group on Radio Diagnostics of Space Weather Plasma Processes – Co-Chair: 2021 – Present
  • Engineering Institute of Canada Strategic Conference Planning Committee – Member: 2020 – Present
  • International Union of Radio Science (URSI): Canadian National Committee (CNC) Chair for Commissions G (Ionospheric radio and propagation) and H (Waves in plasmas): Jan, 2020 – Dec, 2027 (2x4-year terms)
  • COSPAR International Space Weather Action Teams (ISWAT) G2b-04, G2b-05, G2b-06, and S03-03 - Member: December 2019 – Present
  • Canadian Association of Physicists (CAP) Division of Atmospheric and Space Physics (DASP) - Vice Chair: Feb, 2019 – 2022; Chair: Feb, 2022 – Present
  • Abdus Salam International Centre for Theoretical Physics (ICTP) NeQuick Model Working Group - Inaugural Member: Oct, 2019 – Present
  • International Association of Geomagnetism and Aeronomy (IAGA) - Canadian Senior National Representative: Sept, 2018 – Jan 2029 (2-year term + 2-year term + 4-year term + 4-year term)
  • International Reference Ionosphere (IRI) Working Group - Member/Canadian National Representative: July, 2018 – Present

Publications

Recent publications

Article

Aylett, T, Feng, W, Marsh, DR, Themens, D & Plane, JMC 2025, 'Characteristics of Sporadic E Layer Occurrence in a Global Chemistry-Climate Model: A Comparison With COSMIC-Derived Data', Journal of Geophysical Research: Space Physics, vol. 130, no. 1, e2024JA033044. https://doi.org/10.1029/2024JA033044

Thayaparan, T & Themens, DR 2025, 'Emerging Trends in Radar: long-range surveillance in North Polar Region', IEEE Aerospace and Electronic Systems Magazine. https://doi.org/10.1109/MAES.2025.3535436

Reidy, JA, Kavanagh, AJ, Häggström, I, Themens, DR & Wild, M 2025, 'Generating electron density archives using mainland EISCAT data between 2001 and 2021 at 10 min and 1 h integration', RAS Techniques and Instruments, vol. 4, rzaf003. https://doi.org/10.1093/rasti/rzaf003

Vadas, SL, Themens, DR, Huba, JD, Becker, E, Bossert, K, Goncharenko, L, Maguire, SJ, Figueiredo, CAOB, Xu, S, Harvey, VL, Frissell, NA, Molzen, MJ, Pisano, TJ & Nykiel, G 2025, 'Higher-Order Gravity Waves and Traveling Ionospheric Disturbances From the Polar Vortex Jet on 11–15 January 2016: Modeling With HIAMCM-SAMI3 and Comparison With Observations in the Thermosphere and Ionosphere', Journal of Geophysical Research: Space Physics, vol. 130, no. 1, e2024JA033040. https://doi.org/10.1029/2024JA033040

Günzkofer, F, Stober, G, Kero, J, Themens, DR, Tjulin, A, Gulbrandsen, N, Tsutsumi, M & Borries, C 2025, 'Indications for particle precipitation impact on the ion-neutral collision frequency analyzed with EISCAT measurements', Annales Geophysicae, vol. 43, no. 1, pp. 331-348. https://doi.org/10.5194/angeo-43-331-2025

Thayaparan, T, Chiu, M & Themens, DR 2025, 'Modeling the Impact of Sporadic-E on Over-the-Horizon Radar (OTHR) in the Polar Region', IEEE Geoscience and Remote Sensing Letters, vol. 22, 7506805. https://doi.org/10.1109/LGRS.2025.3576665

Elvidge, S & Themens, D 2025, 'The Probability of the May 2024 Geomagnetic Superstorm', Space Weather, vol. 23, no. 1, e2024SW004113. https://doi.org/10.1029/2024SW004113

Reid, B, Themens, DR, Mccaffrey, A, Jayachandran, PT, Hoque, M & Mazzella, AJ 2024, 'GNSS Differential Code Bias Determination Using Rao‐Blackwellized Particle Filtering', Space Weather, vol. 22, no. 5, e2023SW003611. https://doi.org/10.1029/2023SW003611

Kunduri, BSR, Baker, JBH, Ruohoniemi, JM, Thomas, EG, Huba, JD, Emmons, DJ, Themens, DR, Sterne, KT, Farinas Perez, G, Bristow, WA, Shepherd, SG, Holmes, JM, Dao, EV, Chartier, AT, Perry, GW & Pandey, K 2024, 'HF Radar Observations and Modeling of the Impact of the 8 April 2024 Total Solar Eclipse on the Ionosphere-Thermosphere System', Geophysical Research Letters, vol. 51, no. 24, e2024GL112484. https://doi.org/10.1029/2024GL112484

Ruck, JJ, Themens, DR, Ponomarenko, P, Burrell, AG, Kunduri, B, Ruohoniemi, JM & Elvidge, S 2024, 'On the Use of SuperDARN Ground Backscatter Measurements for Ionospheric Propagation Model Validation', Space Weather, vol. 22, no. 9, e2024SW003916. https://doi.org/10.1029/2024sw003916

Conference contribution

Elvidge, S, Reid, B & Themens, DR 2024, Assimilation of Radio Occultation Bending Angles in a Global Ionospheric Model. in 2024 4th URSI Atlantic Radio Science Meeting (AT-RASC)., Th-G03-PM1-1, URSI, 4th URSI Atlantic Radio Science Conference, Gran Canaria, Spain, 19/05/24. https://doi.org/10.46620/URSIATRASC24/FFLA3909

Letter

Thomas, EG, Shepherd, SG, Kunduri, BSR & Themens, DR 2024, 'Multi-Frequency SuperDARN HF Radar Observations of the Ionospheric Response to the October 2023 Annular Solar Eclipse', Geophysical Research Letters, vol. 51, no. 24, e2024GL112450. https://doi.org/10.1029/2024GL112450

Paper

Elvidge, S & Themens, DR 2024, 'A Probabilistic Approach for T-Scale Development', Paper presented at 45th COSPAR Scientific Assembly, Busan, Korea, Republic of, 13/07/24 - 21/07/24.

Elvidge, S, Healy, S, Culverwell, I & Themens, D 2024, 'Assimilation of Radio Occultation Bending Angles in a Global Ionospheric Model', Paper presented at 8th EUMETSAT ROM SAF Workshop on GNSS RO Measurements, Reading, United Kingdom, 11/06/24 - 13/06/24.

Preprint

Reid, B, Themens, DR, Elvidge, S, Ahmed, MA, Wong, J & Ball, W 2024 'AIDA: A Real-Time Global Ionosphere/Plasmasphere Data Assimilation Model' ESS Open Archive. https://doi.org/10.22541/essoar.170516089.91436324/v1

View all publications in research portal